/*
** $Id: llex.h,v 1.79 2016/05/02 14:02:12 roberto Exp $
** Lexical Analyzer
** See Copyright Notice in lua.h
*/

#ifndef llex_h
#define llex_h

#include "lobject.h"
#include "lzio.h"


#define FIRST_RESERVED  257


#if !defined(LUA_ENV)
#define LUA_ENV     "_ENV"
#endif


/*
* WARNING: if you change the order of this enumeration,
* grep "ORDER RESERVED"
*/
enum RESERVED {
    /* terminal symbols denoted by reserved words */
    TK_AND = FIRST_RESERVED, TK_BREAK,
    TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
    TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
    TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
    /* other terminal symbols */
    TK_IDIV, TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE,
    TK_SHL, TK_SHR,
    TK_DBCOLON, TK_EOS,
    TK_FLT, TK_INT, TK_NAME, TK_STRING
};

/* number of reserved words */
#define NUM_RESERVED    (cast(int, TK_WHILE-FIRST_RESERVED+1))


typedef union {
    lua_Number r;
    lua_Integer i;
    TString* ts;
} SemInfo;  /* semantics information */


typedef struct Token {
    int token;
    SemInfo seminfo;
} Token;


/* state of the lexer plus state of the parser when shared by all
   functions */
typedef struct LexState {
    int current;  /* current character (charint) */
    int linenumber;  /* input line counter */
    int lastline;  /* line of last token 'consumed' */
    Token t;  /* current token */
    Token lookahead;  /* look ahead token */
    struct FuncState* fs;  /* current function (parser) */
    struct lua_State* L;
    ZIO* z;  /* input stream */
    Mbuffer* buff;  /* buffer for tokens */
    Table* h;  /* to avoid collection/reuse strings */
    struct Dyndata* dyd;  /* dynamic structures used by the parser */
    TString* source;  /* current source name */
    TString* envn;  /* environment variable name */
} LexState;


LUAI_FUNC void luaX_init( lua_State* L );
LUAI_FUNC void luaX_setinput( lua_State* L, LexState* ls, ZIO* z,
                              TString* source, int firstchar );
LUAI_FUNC TString* luaX_newstring( LexState* ls, const char* str, size_t l );
LUAI_FUNC void luaX_next( LexState* ls );
LUAI_FUNC int luaX_lookahead( LexState* ls );
LUAI_FUNC l_noret luaX_syntaxerror( LexState* ls, const char* s );
LUAI_FUNC const char* luaX_token2str( LexState* ls, int token );


#endif
